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3 years ago

Please answer need help for a quiz

Mathematics

1 answer:

Paul [167]3 years ago

4 0

Answer:

option B

Step-by-step explanation:

$3i( - 4 + 2i)$

$= > 3i \times ( - 4) + 3i \times 2i$

$= > - 12i + 6 {i}^{2}$

But it's given that ${i}^{2} = - 1$

So,

$- 12i + 6 {i}^{2} = - 12i + 6 \times ( - 1) \\ \: \: \: \: \: \: \: \: \: = - 12i - 6$

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If the radius of a cylinder was shrunk down to a quarter of its orignal size and the height was reduced to a third of its origin

svetoff [14.1K]

The modified area is (1/48) (2πr(4h+3r))

Step-by-step explanation:

Let the radius be 'r' and height be 'h'.

Area of cylinder= 2π r(h+r)

The radius is shrunk down to quarter of its original radius

r = r/4

The height is reduced to a third of its original height

h = h/3

New Area = 2π(r/4) [(h/3) +(r/4) ]

= (1/4)2πr[(4h+3r) /12]

= (1/48) (2πr(4h+3r))

6 0

3 years ago

Can i get your help please Simplify: 176/14

erastova [34]

Answer:

$12\frac{8}{14}$ or 12.57

Step-by-step explanation:

$12\frac{8}{14}$ or 12.57

4 0

3 years ago

Read 2 more answers

sin alpha = 7/25, alpha lies in quadrant ii, and cos beta = 2/5, beta lies in quadrant i. find cos(alpha-beta).

Ilia_Sergeevich [38]

Answer:

Therefore $\cos(\alpha-\beta)=\frac{48+7\sqrt{25}}{125}$

Step-by-step explanation:

Given values are

$\sin \alpha=\frac{7}{25}$

$\cos \beta=\frac{2}{5}$

$\sin^2x+\cos^2=1$

$\cos \alpha=\sqrt{1-\sin^2\alpha}$

$\cos \alpha=\sqrt{1-(\frac{7}{25})^2}$

$\cos \alpha=\sqrt{1-\frac{49}{625}}$

$\cos \alpha=\sqrt{\frac{576}{625}}$

$\cos \alpha=\frac{24}{25}$

$\sin \beta=\sqrt{1-\cos^2\beta}$

$\sin \beta=\sqrt{1-(\frac{2}{5})^2}$

$\sin \beta=\sqrt{1-\frac{4}{25}}$

$\sin \beta=\frac{\sqrt{21}}{5}$

$\cos(\alpha-\beta)=\cos\alpha\cos\beta+\sin\alpha\sin\beta$

$\cos(\alpha-\beta)=\frac{24}{25}\times\frac{2}{5}+\frac{7}{25}\times\frac{\sqrt{21}}{5}$

$\cos(\alpha-\beta)=\frac{48+7\sqrt{25}}{125}$

7 0

3 years ago

Could anyone help me out with this?

Mama L [17]

Answer: they are abt the same its all abt percentage now- Pitcher A

Step-by-step explanation: more water lessens the strength

7 0

3 years ago

6.2×0.03= and tell me how you did it please

matrenka [14]

Answer:

0.186

Step-by-step explanation:

6.2

x 0.03

6.2

x 0.03 since 6*3=18, we have to carry the 1

6.2

x 0.03

186

6.2

x 0.03

186

6.2

x 0.03

186

6.2

x 0.03

186

6.2

x 0.03

186

+ 00 add the partial products

00

00186

6.2

x 0.03 count how many digits are after the decimal point from each factor =3 and place in product

186

+ 00

00

00.186=0.186

answer=0.186

8 0

3 years ago